This invention relates to improvements in the connection between a cross members or bolster and side members or side frames of railway trucks.
Recent studies proved that the areas where the longitudinal side members are connected to the cross member of a rigid-type bogie-truck as used in railway stock travelling at relatively high speed were the seat of multiple stresses, notably vertical and horizontal flexion stresses, tractive efforts and torsional stresses. In the last few years various improvements have been brought to this side-members to cross-member junction notably by changing from the construction in which the cross member was fitted into a suitable aperture formed in the side members, to the construction in which the side members and the cross member are joined by butt welding so as to cause the weld seam to emerge from the area where maximum stress concentrations are registered. This type of joining is disclosed notably in U.S. Pat. Application Ser. No. 660,131 filed Feb. 23, 1976 by the same Applicant. However, it appeared that the efficiency of this construction, notably as far as the strength and useful life of the final junction are concerned, was subordinated to a great extent to the shape of the end portion of the cross member in the junction area and that the shapes contemplated up to now did not afford a fully satisfactory stress distribution.